Mark William Knowles (born 10 March 1984) is the Australian field hockey captain. He has played professional hockey in the Netherlands for HC Rotterdam. He plays for the Queensland Blades in the Australian Hockey League. He has been the captain of the Australia men's national field hockey team the Kookaburras since 2014. He won a gold medal at the 2004 Summer Olympics, the 2014 World Cup, the 2005 and 2012 Champions Trophy. Knowles' most recent achievement was runner-up in the 2021 Brisbane Hockey League Division 2 Grand Final.